Schistosomiasis
Schistosomiasis, also known as bilharzia, is a disease caused by parasitic worms.Sometimes be commonly called swimmer's itch.Infection with Schistosoma mansoni, S. haematobium , and S. japonicum causes illness in humans. Although schistosomiasis is not found in the United States, 200 million people are infected worldwide. Infection occurs when your skin comes in contact with contaminated fresh water in which certain types of snails that carry schistosomes are living. Fresh water becomes contaminated by Schistosoma eggs when infected people urinate or defecate in the water. The eggs are responsible for much of the pathology associated with the disease. The eggs hatch, and if certain types of snails are present in the water, the parasites grow and develop inside the snails. The eggs pass through the walls of the mesenteries, and through the intestinal walls into the gut lumen.They achieve this is still not well understood, however, it is likely to be a result of a number of interacting factors. Factors such as the mechanical action of the egg spine, acted upon initially, by the host blood pressure and then by the peristaltic action of the gut help drive the egg into and through the tissues. In addition, the miracidium within the egg has been shown to release proteolytic enzymes which may help it digest its way through the host tissue.
The host inflammatory reaction, which is a delayed type hypersensitivity reaction and which forms a granuloma around the egg, also seems to be essential for successful migration of the egg to the lumen of the intestine. Persons who travel to endemic areas. As well as among resident expatriates, such as Peace Corps volunteers in high-risk areas. Those at greatest risk are travelers who wade, swim, or bathe in fresh water in areas where sanitation is poor and the snail hosts are present. This infection occurs widely throughout the tropics and subtropics, affecting some 200 million persons. Schistosomiasis is most prevalent in sub-Saharan Africa.In highly endemic areas, prevalence rates can exceed 50% among the local population, and high rates have been reported among expatriates living in such areas. Schistosomiasis control is far more effective when placed in the context of a general health system. The integration process is slow, but this "horizontal" approach is now becoming an integral part of health care at village level.
Causes of Schistosomiasis
Common causes of Schistosomiasis
- Contaminated water.
- Cercaria.
- Schistosoma mansoni.
- Schistosoma haematobium
- Schistosoma intercalatum.
Symptoms of Schistosomiasis
Common symptoms of Schistosomiasis
- Rash.
- Itchy skin.
- Fever.
- Chills.
- Cough.
- Muscle aches.
- Intestine.
- Bladder.
- Liver and spleen enlargement.
Treatment of Schistosomiasis
Common Treatment of Schistosomiasis
- Schistosomiasis is readily treated using a single oral dose of the drug Praziquantel.While Praziquantel is safe and highly effective in curing an infected patient, it does not prevent re-infection by cercariae and is thus not an optimum treatment for people living in endemic areas.
- Antimony has been used in the past to treat the disease. In low doses, this toxic metalloid bonds to sulfur atoms in enzymes used by the parasite and kills it without harming the host.
- A new Egyptian drug, is under investigation for oral treatment of the disease.
- Oxamniquine has been effective in treating infections caused by S. mansoni.
- Vigorous towel drying after an accidental, very brief water exposure may help to prevent the Schistosoma parasite from penetrating the skin.
- Drainage of marsh areas where snails breed.
- Education.
- The use of molluscicides.
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